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161.
Agriculture is one of the prime activities of the hill people residing in the northwestern Indian Himalaya. However, poor soil fertility in these areas is a big hurdle to sustainable farming. The effects of washout of topsoil and its nutrients, year after year, due to the abundance of snowfall, avalanches, landslides and erosion further add to the woes of the farmers. In the cold and harsh climatic conditions of the region, with grass and vegetation cover being scanty, it is not possible to maintain large herds of cattle for the adequate production of farmyard manure. Faced with this situation, the locals have relied heavily on obtaining organic manure derived from composting of human excreta. In earlier times the dire necessity of the farmers helped them overcome the revulsion associated with the practice of handling human excreta, but now with the advent of modernisation and the easy availability of chemical fertilisers, the people are distancing themselves from this age-old practice. More and more people are opting for modern toilets and leaving behind the traditional toilets that made possible the harvesting of manure from night-soil. As a result, this primitive practice is on the verge of extinction. This eco-friendly practice, that has sustained the land for so many generations, needs to be continued and strengthened as the long-term consequences of excessive and indiscriminant use of chemical fertilisers are becoming too obvious to ignore. Traditional knowledge needs to be combined with modern scientific know-how to make this practice safer and more acceptable. If the composting operation is managed properly, the handling will be less loathsome and the concerns of health and hygiene too will stand addressed. The present study attempts a detailed profile of the practice of 'supplementing soil nutrients through biocomposting of night-soil' in the cold desert region of Lahaul Valley. Four villages running from the northwestern part to the southeastern part of the valley were selected. The study is broadly based on a direct interview of heads of the various households in the selected villages of Kuthar (2600m), Hinsa (2700m), Jahlma (3000m) and Khoksar (3200m).  相似文献   
162.
The effects of air pollution on plants downwind of a fertilizer factory at Udaipur, India, were studied using three woody perennials. Seedlings of these species including a shrub (Carissa carandas L.), a leguminous avenue tree (Cassia fistula L.) and a fruit tree (Psidium guajava L.) were grown in earthen pots at different study sites receiving varying levels of air pollution input. Changes in plant growth, morphological characteristics, photosynthetic pigment, ascorbic acid, N and S contents and in dry matter allocation were considered in relation to the status of ambient air quality. Observations with these parameters have indicated that the ambient air around the factory contained pollutants at phytotoxic levels. Plant height, basal diameter, conopy area, leaf area and chlorophyll, ascorbic acid and foliar-N concentrations decreased with increasing pollution load. However, foliar-S increased slightly at polluted sites. Air pollution load around the factory have also altered the biomass allocation. Root:shoot ratios increased in C. fistula and P. guajava at polluted sites. In contrast, for C. carandas the above ground parts, where foliage assumed predominance showed precedence over the root growth. This species responded characteristically to air pollution stress by allocating more of its photosynthate towards leaf production and shoot growth.  相似文献   
163.
In view of their sensitivity and importance, an ecological-economic analysis of wetlands has been carried out for various Indian states. Subsequently, the ecological wealths of different zones (north, south, east and west) have been computed and compared. Amongst states, Karnataka (7896.5 million US dollars yr(-1)), Gujarat (7689.4 million US dollars yr(-1)) and Andhra Pradesh (7670.9 million US dollars yr(-1)) are found to be the richest, whereas Nagaland (3.1 million US dollars yr(-1)), Meghalaya (5.9 million US dollars yr(-1)) and Sikkim (15.9 million US dollars yr(-1)) turn out to be the poorest. Amongst different zones, Southern Zone turns out to be the richest and the Northern Zone poorest. A ratio called ANR [Artificial (A) Wetland Wealth to Natural (N) Wetland Wealth Ratio (R)] has also been devised, which is the ratio of the ecological-economic values of artificial and natural wetlands. In other words, this ratio indicates the level of environmental concern of a given region. ANR ratio is found to be the highest for Madhya Pradesh (564.1) and Karnataka (159.8) states.  相似文献   
164.
Environment, Development and Sustainability - Trees are important as a source of fuelwood and fodder for rural populations in the Himalayas. This paper analysed the fuelwood and fodder consumption...  相似文献   
165.
The present work deals with the determination of uranium concentrations in drinking and ground water samples by laser fluorimetry and calculation of cumulative, age-dependent radiation doses to humans. The concentrations were found to be between 0.20 ± 0.03 and 64.0 ± 3.6 μg L?1, with an average of 11.1 ± 1.5 μg L?1, well within the drinking water limit of regulatory bodies. The concentrations of uranium increase with depth of water samples collection. The estimated annual ingestion dose due to the intake of uranium through drinking water for all age groups varied between 0.2 and 137 μSv a?1, with an average of 17.3 μSv a?1. The mean annual ingestion dose is 5% of the global average ingestion dose, for infants, marginally higher than for other age group. Most effective dose values were less than 20 μSv a?1.  相似文献   
166.
The effect of antioxidant rich diet supplements of Spirulina and tamarind fruit pulp at 230 mg kg?1 body weight, separately as well as in combination, on various hematological parameters of Swiss albino mice exposed to fluoride for seven days at daily doses of 190 mg kg?1 body weight and for 90 days at daily doses of 94 mg kg?1 body weight is reported. Compared with controls, fluoride exposure decreased erythrocyte (12%–18%), leukocyte (16%) and platelet counts (7%, only for short-term exposure), hemoglobin (2%–17%) and packed cell volume (2%–14%) in Swiss albino mice reared on standard feed but these were altered little in the diet supplement groups. Fluoride exposure decreased lymphocytes in both standard feed (16%–21%) and diet supplement groups (5%–19%, but only after long-term exposure). Fluoride withdrawal led to recovery of the post-treated mice from long-term exposure. Spirulina alone and also in combination with tamarind fruit pulp was found more effective than tamarind alone in reducing hematological disorders in fluoride treated mice.  相似文献   
167.
Metal containing wastes/byproducts of various industries, used consumer goods, and municipal waste are potential pollutants, if not treated properly. They may also be important secondary resources if processed in eco-friendly manner for secured supply of contained metals/materials. Bio-extraction of metals from such resources with microbes such as bacteria, fungi and archaea is being increasingly explored to meet the twin objectives of resource recycling and pollution mitigation. This review focuses on the bio-processing of solid wastes/byproducts of metallurgical and manufacturing industries, chemical/petrochemical plants, electroplating and tanning units, besides sewage sludge and fly ash of municipal incinerators, electronic wastes (e-wastes/PCBs), used batteries, etc. An assessment has been made to quantify the wastes generated and its compositions, microbes used, metal leaching efficiency etc. Processing of certain effluents and wastewaters comprising of metals is also included in brief. Future directions of research are highlighted.  相似文献   
168.
The waste water showed high values of total solid (TS), hardness and chloride with slightly alkaline pH along with high concentrations of Cr (2.03 mg l(-1)), Ni (1.59 mg l(-1)) and Zn (0.46 mg l(-1)). The concentration of Cu (0.21 mg l(-1)) and Zn in industrial waste water was low than Ni and Cr. The diluted (25 and 50%), undiluted (100%) waste water was used to irrigate the lettuce plants grown in alluvial soils. Plants accumulated heavy metals in their shoot (Ni, 13.65; Cr, 19.73; Zn, 21.6 and Cu 14.76 microg g(-1) dry weight) and root (Ni, 41.4; Cr, 31.6; Zn, 30.2 and Cu 15.85 microg g(-1) dry weight) in high concentrations after irrigation with undiluted industrial waste water. Maximum accumulation of heavy metals was found in the root than the shoot (13.65-21.60 microg g(-1) dry weight). Dry matter yield and biomolecules (Chlorophyll a, b and sugar contents) was found to increase with increase in concentration of waste water up to 50%, which declined at the exposure of undiluted waste water. Catalase activity was found to increase with increase in waste water concentrations up to 100%, while carotenoids content increased in plants only up to the 50% waste water irrigation. Use of industrial waste water in such form, on agricultural lands is not found suitable without proper treatment. It could be injurious to plants growth and may be a potential threat to food web.  相似文献   
169.
This study was aimed at determining microbial biomass at land water interface and the role it plays in regulating ecosystem properties of a fresh water dry tropical woodland lake. Four microbial variables namely biomass-C (Cmic), fumigated CO2-C, substrate induced respiration (SIR) and basal respiration (BR) were measured in humus samples collected from land water interface over a period of one year Microbial biomass (Cmic) was maximum during February (718 micorg CO2-C g(-1)). Similar was the case of fumigated CO2-C (560 microg CO2-C g(-1) 10 d(-1)), SIR (2900 microg CO2-C g(-1)) and BR (480 microg CO2-C g(-1)). Humus-N appeared maximum (1.60%) during November and phenolics (204 microg g(-1)) during December Gross primary productivity (GPP) was found maximum (3.30 g Cm(-2)d(-1)) during March. Almost similar trend appeared for chlorophyll and phytoplankton density. Variation in microbial biomass at land water interface can be explained by seasonality and the quality of substrate material. Asynchrony in the peaks of microbial variables with phytoplankton pulsation and GPP suggested that the microbial biomass through nutrient mineralization regulates ecosystem functioning of a fresh water woodland lake. This has relevance for evaluating the nature of anthropogenic perturbations and for maintenance of fresh water lakes void of human disturbances.  相似文献   
170.
The effluent from a Lucknow- based distillery (Mohan Meakin Distillery) was analyzed for physico-chemical and biological parameters of pollution and concentration of potentially toxic heavy metals (Cd, Cr, Ni and Zn) and the effect of the distillery effluent, as such and on 50% dilution with tap water was studied on seed germination and seedling growth of maize (Zea mays L.) and rice (Oryza sativa L.). The effluent was wine red in colour and highly acidic (pH approximately 55) and possessed decaying alcoholic smell. The effluent contained high values of different pollution parameters, particularly total solids, 3450 mgl(-1) (soluble plus suspended solids), alkalinity 1500 mgl(-1), biological oxygen demand (BOD, 1649 mgl(-1)) and chemical oxygen demand (COD, 2036 mgl(-1)). It had very low values of dissolved oxygen (DO, 0.34 mgl(-1)). The heavy metals (Cd, Cr, Ni and Zn) content, particularly the nickel concentration (0.029 mg l(-1)) was high. Use of the distillery effluent, even on 1:1 dilution with tap water inhibited germination and early seedling growth of maize and rice. In both maize and rice, more so in the former germination % of seeds, length of radicle and plumule and the fresh and dry weight of the seedlings were significantly reduced. The emerging leaves of the seedlings also developed visible effects of toxicity some of which resembled the symptoms of nickel toxicity. Our observations suggest that the effluent, as discharged from the distillery carry a heavy load of pollutants. Its discharge into the river Gomti poses a potential threat to the aquatic life, perticularly during the summer months when the water flow in the river is drastically reduced. The distillery effluentis also harmful for irrigating crops grown along the drain carrying it.  相似文献   
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